http://news.bbc.co.uk/2/hi/uk_news/e...et/5334208.stm


Wearing helmets 'more dangerous'

Cyclists who wear protective helmets are more likely to be knocked down
by passing vehicles, new research from Bath University suggests.

The study found drivers tend to pass closer when overtaking cyclists
wearing helmets than those who are bare-headed.

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To carry out the research, Dr Walker used a bike fitted with a computer
and an ultrasonic distance sensor to find drivers were twice as likely to
get close to the bicycle, at an average of 8.5cm, when he wore a helmet.

The experiment, which recorded 2,500 overtaking motorists in Salisbury
and Bristol, was funded by the Engineering and Physical Sciences Research
Council.

Dr Walker, a traffic psychologist from the University's Department of
Psychology, said: "This study shows that when drivers overtake a cyclist,
the margin for error they leave is affected by the cyclist's appearance.

"By leaving the cyclist less room, drivers reduce the safety margin that
cyclists need to deal with obstacles in the road, such as drain covers
and potholes, as well as the margin for error in their own judgements.

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To test another theory, Dr Walker donned a long wig to see whether there
was any difference in passing distance when drivers thought they were
overtaking what appeared to be a female cyclist.

While wearing the wig, drivers gave him an average of 14cm more space
when passing.

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